Nozzle



arch 19, 1968 O. A. DAVIS, SR

NOZZLE Filed Feb. 5, 1966 United States Patent. f

poration of Delaware Filed Feb. 3, 1966, Ser. No. 524,672 12 Claims.(Cl. 239291) This invention relates to spray nozzles such as oil burnernozzles. More particularly, it relates to nozzles for producing a sprayof a primary fluid, such as fuel oil, having means for introducing a jetor a plurality of disjunct jets of a secondary fluid, such as air, tothe periphery of said spray or the flame produced upon combustionthereof without permitting said jet or jets to divide or split the sprayof primary fluid or the flame produced upon combustion thereof uponimpingement thereon.

Conventional oil burner nozzles have a swirl chamber wherein liquid oilis swirled as a thin film at high velocity. Upon discharge from thedischarge orifice of the swirl chamber, the swirling film is suddenlyreleased from the confines of the swirl chamber wall surface whereuponit disintegrates into a spray of highly atomized oil droplets. The sprayis substantially circular in cross section and, upon ignition, theresulting flame is also circular in transverse section.

In conventional nozzles wherein one or more separate jets of pressurizedgas, such as air, are charged from within the spray nozzle to theperiphery of an atomized spray or the flame produced upon combustionthereof, the pressurized jets travel at a high velocity and penetratethe spray, or the flame produced upon combustion thereof, and split ordivide it at the point of impingement. In accordance with the presentinvention, a single relatively narrow jet or a plurality of disjunctnarrow jets of pressurized air are charged directly to the periphery ofthe flame produced by the nozzle oil spray substantially without saidair jets splitting the body of said flame. In the practice of thisinvention each jet of pressurized air reaching the flame is theresultant of two substantially equal streams of pressurized air whichare charged at high velocity and pressure in a collision course directlyinto each other and the impact of the two high velocity streams occursclose to a lateral nozzle opening or passageway which is in closeproximity to and facing the periphery of the flame. Following the highvelocity impact of the two colliding air streams, a resultant streamisformed having a substantial pressure but having a very low velocity as aresult of the impact. Since the lateral resultant stream travels towardthe periphery of the flame at a low velocity, impingement thereof uponthe flame does not split the flame. The two colliding air streams priorto impact travel in channels directed substantially transverse withrespect to but offset from the longitudinal axis of the nozzle. Thestream formed as a result of impact is charged in a direction which issubstantially radial but which can also be somewhat forwardly withrespect to the nozzle axis.

The nozzle of this invention has particular utility for use as an oilburner nozzle for flame wedding. When utilizing a flame to destroy weedsgrowing along the ground near desired crops, it is customary to attach aseries of burners to the rear of a tractor. The burners are arranged ina row laterally along the rear of the tractor and spaced apart from eachother by a distance corresponding to the spacing between the rows ofcrops. The

flame weeder burners are inclined downwardly at an angle.

toward the ground at the side of a row of growing crops so that as thetractor travels in the direction of the row the flame can scorch anyground weeds growing in the vicinity of the crops. In order to confinethe flame to the ground with a minimum of impingement upon the upper3,373,941 Patented Mar. 1 9, 1968 regions of the desired plant which areparticularly heat sensitive because they contain the foliage and flowerof the plant, the flame is advantageously oblong, being flattened orelongated in the direction of movement of the tractor. By utilizing anozzle of this invention, a flattened or oblong flame is producedwithout splitting the flame or otherwise destroying the uniform texturethereof by compressing the flame between a pair of low velocitypressurized air streams, each of said pair of air streams being theresultant of a pair of colliding air streams as described above. Two airstreams collide in the nozzle on one side of the burner flame to producea resulting low velocity jet thereat while two other air streams collidein the nozzle on the diametric opposite side of the flame to produce asecond low velocity jet thereat. These two low velocity jets aredirected axially outwardly toward the periphery of the flame,sandwiching the flame therebetween, and compressing said flame toproduce an oblong flame configuration without fracturing said flame. Theoblong flame thus produced is highly suitable for purposes of flameweeding.

This invention is further explained by reference to the accompanyingdrawings in which:

FIGURE 1 is a longitudinal sectional view of an assembled burner nozzleof this invention,

FIGURE 1A is a view of the flame produced by the nozzle of FIGURE 1 asseen from the position 1A1A of FIGURE 1,

FIGURE 2 is an exploded view of certain elements of the nozzle of FIGURE1,

FIGURE 3 is a plan view of the interior of nozzle element 26,

FIGURE 4 is a plan view of the exterior of nozzle element 26, and

FIGURE 5A is an isometric view of a segment of the front face of element26 showing the flame configuration produced during combustion therewith.FIGURES 5B and 5C are isometric views of the corresponding region of twonozzles not of the present invention showing their respective flameconfigurations to illustrate the advantageous effect upon flameconfiguration accomplished with the nozzle of this invention.

Referring to both FIGURES 1 and 2, inner conical member 10 has a conicalsurface 12 having a plurality of slanted surface slots 14. Inner member10 also has a central bore 11 and lateral passageways 13 radiatingtherefrom. Intermediate conical member 16 has an interior conicalsurface 18, an exterior conical surface 19, a forward axial orifice 20having a curved and tapered surface, and an upper ledge 22. Conicalsurface 12 of inner conical member 10 abuts in fluid-tight engagementagainst interior conical surface 18 of intermediate conical member 16 todefine swirl chamber 24 therebetween.

Outer conical member 26 is shown in side view in FIGURES land 2 and isshown in interior plan view in FIGURE 3 and exterior plan view in FIGURE4. The inner surface 28 of outer member 26 is conical while the outsidesurface 30 is flat. Axial opening 32 defines an elongated dischargeorifice. The exterior of orifice 32 is at the center of groove 34 whichis cut into the flat surface 30. The interior of orifice 32 issandwiched between a pair of parallel arcuate grooves or slots 36 and 38and is disposed at the center of said parallel grooves. As indicated inFIGURES 3 and 4, exterior groove 34 becomes substantially contiguouswith interior grooves 36 and 38 at the elongated sides of orifice 32.Interior conical surface 28 of outer member 26 abuts in fluid-tightengagement against outer conical surface 19 of intermediate member 16 todefine enclosed channels of slots 36 and 38 and to define a smallchamber 40.

The conical surfaces of inner conical element 10, intermediate conicalelement 16 and outer conical element 26 are in fluid-tight abuttingengagement in the assembled nozzle, as shown in FIGURE 1. In assemblingthe nozzle, hollow interior plug 42 is screwed into outer nozzle body44. Interior plug 42 has a central bore 43 into which a set screw 46 isscrewed. Set screw 46 has a central bore 47. When the nozzle isassembled cylindrical prong 48 is pressed tightly against ledge 22 ofelement 16 by screwing threaded shoulder 50 into nozzle body 44.Threaded shoulder 50 has a plurality of longitudinal passageways 51extending therethrough. Set screw 46 is then urged tightly againstmember 10 by utilizing an elongated wrench in hex 52.

In the assembled nozzle a passageway 54 is defined between member 10 andprong 48 of plug 42. Another passageway 56 is defined between prong 48of plug 42 and nozzle body 44. The assembled nozzle is screwed into anadaptor 58 having a lateral fuel oil inlet passageway 60 and an axialpressurized air inlet passageway 62. The oil and air passageways aresealed off from each other by means of O-ring 63.

In the operation of the nozzle, fuel oil under a pressure of about 80 to100 pounds per square inch is charged through passageways 60, 43, 47,11, 13 and 54 to tangential slots 14. Tangential slots 14 cause the oilto swirl as a thin film within swirl chamber 24. When the swirling filmis discharged through orifice 20 and thereby released from the confinesof conical surface 18 it disintegrates and becomes atomized into smalldroplets of oil in a conical diverging spray. Upon ignition, theresulting flame has a configuration as indicated at 64.

Pressurized air at a pressure of between about 30 and 50 pounds persquare inch is charged through passageways 62, 51 and 56. In annularpassageway 56 the pressurized air is admitted to opposite ends of eacharcuate channel or groove 36 and 38 so that the air destined to travelthrough each groove is divided into substantially equal portions, thefirst of which enters its groove from one end thereof and the second ofwhich enters the same groove from hte opposite end thereof. The twoportions of air flow toward each other in a collision course fromopposite ends of the same groove as indicated in FIG- URES 1A, 3, 4 andA by arrows 66 and 68 in groove 36 and arrows 70 and 72 in groove 38.The momentum of impact of streams 66 and 68 in groove 36 and streams 70and 72 in groove 38 is great because it is established by the impact oftwo moving streams and results in stopping the forward movement of thecolliding streams. Thereupon, air streams 66 and 68 combine to form anew stream 74 which travels in a direction which is 90 degrees lateralwith respect to streams 66 and 68. Similarly, air streams 70 and 72combine to form a new stream 76 which travels in a direction which is 90degrees lateral with respect to streams 70 and 72. Because streams 74and 76 are each the resultant of two streams colliding head-on at highvelocity, streams 74 and 76 at the moment of formation have a relativelylow velocity and therefore are capable of flattening the opposite endsof flame 64 without otherwise violently disrupting flame 64, as shown inFIGURE 1A.

The comparative flame configurations presented in FIGURES 5A, 5B and 5Cillustrate the advantageous effect of parallel grooves 36 and 38. FIGURE5A is an isometric view of a segment of the front face 30 of element 26showing the flame configuration produced during combustion. FIGURES 5Band 5C are isometric views of the corresponding region of two nozzlesnot of the present invention showing their respective flameconfigurations. Referring first to FIGURE 5B, front face 30 of anelement 26 is shown which differs from element 26 of the nozzle of thisinvention in that it possesses no grooves corresponding to grooves 36and 38. Element 26' therefore does not admit pressurized air and a flame64' is produced which has a conventional round cross-sectionalconfiguration.

Referring next to FIGURE 5C, front face 30" of ele- 4 ment 26" is shownwhich differs from element 26 of the nozzle of the invention byemploying a pair of grooves 78 and 80 which approach the axial dischargeorifice radially. Approach of high velocity air streams 82 and 84 from aradial direction permits streams 82 and 84 to impinge upon oppositesides of flame 86 at a very high velocity and impart a fissure 88 in theflame, thereby splitting flame 86 into two segments. This is contrastedto the operation of the nozzle of the invention, as shown in FIGURE 5A,wherein the air streams impart a flattened configuration to the flameWithout creating a fissure therein. As shown in FIGURE 5A, air streams66 and 68 collide with each other to form a lateral air stream 7 4having a very low velocity. Streams 70 and 72 collide with each other toform a resulting lateral air stream 7 6 whose velocity is also very low.Air streams 74 and 76, each having a low velocity, are directed towardthe opposite sides of flame 64 to convert the flame from a roundconfiguration as shown in FIGURE SE to the oblong configuration shown inFIGURE 5A, without dividing the flame into two segments as shown inFIGURE 5C.

Various changes and modifications can be made without departing from thespirit of this invention and the scope thereof as defined in thefollowing claims.

I claim:

1. A nozzle comprising first means for discharging an axial spray,second means in said nozzle for charging a pressurized fluid in thedirection of the periphery of said spray, said second means comprisingchannel means for charging separate streams of said fluid in collisioncourse toward each other to form a resultant stream of said fluid havinga low velocity, said second means also comprising passageway means inthe zone of collision of said fluid streams which is substantiallylateral with respect to said channel means to direct said resultantfluid stream in the direction of the periphery of said axial spray.

2. The nozzle of claim 1 wherein said channel means is transverse to andoffset from the longitudinal axis of said nozzle.

3. The nozzle of claim 1 wherein said channel means comprises groovemeans having opposite ends open to said pressurized fluid and saidpassageway means comprises lateral opening means substantially at themiddle of said groove means.

4. The nozzle of claim 1 including a plurality of said second means.

5. The nozzle of claim 1 including a pair of said second meanspositioned for directing a pair of said resultant fluid streams in thedirection of the periphery of said axial spnay on diametrically oppositesides of said spray to impart an oblong configuration to said spraysubstantially without splitting said spray.

6. The nozzle of claim 5 including oblong discharge opening means forthe discharge of said oblong spray.

7. A nozzle comprising first means for discharging an axial spray ofatomized oil droplets, a pair of diametrically oppositely disposedsecond means in said nozzle, said pair of second means positioned forcharging a pair of pressurized air streams in the direction of theperiphery of said spray on diametrically opposite sides thereof forcompressing said spray without imparting a fissure therein, each of saidsecond means comprising groove means extending substantially transverseto and offset from the longitudinal axis of said nozzle and open topressurized air at opposite ends thereof for charging separate streamsof pressurized air in collision course to ward each other to form aresultant stream of pressurized air having a low velocity, passagewaymeans in each groove means comprising a lateral opening substantially atthe middle of each groove means to direct each re-- sultant pressurizedair stream in the direction of the periphery of said oil spray.

8. A burner nozzle comprising an inner conical mem ber, an intermediateconical member, and an outer coni cal member, the conical surfaces ofsaid members ab 5. ting in fluid-tight engagement, axial swirl chambermeans defined by said abutting inner and intermediate members forproducing an atomized spray, air passageway means defined by saidintermediate and outer members, first Opening means at the apex of saidintermediate member defining swirl chamber discharge orifice means,second opening means at the apex of said outer member defining nozzledischarge means, continuous groove means defined by said intermediateand outer members for admitting separate pressurized fluid streams intoopposite ends thereof so that said separate streams approach each otherand collide near the center of said groove means to produce a resultantstream, third opening means substantially at the center of said groovemeans to discharge said resultant stream toward the periphery of saidatomized spray.

9. The nozzle of claim 8 including a plurality of said continuous groovemeans.

10. The nozzle of claim 8 including a pair of said continuous groovemeans disposed in parallel and on opposite sides of said second openingmeans.

11. The nozzle of claim 10 wherein said second opening means iselongated and is substantially contiguous with each of said groove meansalong the elongated sides thereof.

12. A burner n-ozzle comprising an inner conical member, an intermediateconical member, and an outer conical member, the conical surfaces ofsaid members abutting in fluid-tight engagement, axial swirl chambermeans defined by said abutting inner and intermediate members forproducing an atomized oil spray, air passageway means defined by saidintermediate and outer members, first opening means at the apex of saidintermediate member defining swirl chamber discharge orifice means,elongated second opening means at the apex of said outer member definingnozzle discharge means, a pair of parallel continuous groove means inthe abutting conical surface of said outer member disposed on oppositesides of said second opening means, each of said groove means foradmitting separate pressurized air streams into opposite ends thereof sothat said separate air streams approach each other and collide near thecenter of their respective groove means to produce a resultant airstream, a pair of third opening means associated with said pair ofgroove means each substantially at the center of its respective groovemeans to discharge each resultant air stream toward the periphery ofsaid atomized oil spray, said resultant air streams compressing oppositesides of the flame produced upon combustion of said oil spray to producean oblong sectional configuration therein substantially withoutimparting a fissure to said flame.

References Cited UNITED STATES PATENTS 2,587,993 3/1952 Gray 239-296EVERETT W. KIRBY, Primary Examiner.

1. A NOZZLE COMPRISING FIRST MEANS FOR DISCHARGING AN AXIAL SPRAY,SECOND MEANS IN SAID NOZZLE FOR CHARGING A PRESSURIZED FLUID IN THEDIRECTION OF THE PERIPHERY OF SAID SPRAY, SAID SECOND MEANS COMPRISINGCHANNEL MEANS FOR CHARGING SEPARATE STREAMS OF SAID FLUID IN COLLISIONCOURSE TOWARD EACH OTHER TO FORM A RESULTANT STREAM OF SAID FLUID HAVINGA LOW VELOCITY, SAID SECOND MEANS ALSO COMPRISING PASSAGEWAY MEANS INTHE ZONE OF COLLISION OF SAID FLUID STREAMS WHICH IS SUBSTANTIALLYLATERAL WITH RESPECT TO SAID CHANNEL MEANS TO DIRECT SAID RESULTANTFLUID STREAM IN THE DIRECTION OF THE PERIPHERY OF SAID AXIAL SPRAY.